function imageUtil(e) { 
 var imageSize = {}; 
 var originalWidth = e.width;//图片原始宽 
 var originalHeight = e.height;//图片原始高 
 var originalScale = originalHeight/originalWidth;//图片高宽比 
 //获取屏幕宽高 
 wx.getSystemInfo({ 
  success: function (res) { 
   var windowWidth = res.windowWidth; 
   var windowHeight = res.windowHeight; 
   var windowscale = windowHeight/windowWidth;//屏幕高宽比 
   if(originalScale < windowscale){//图片高宽比小于屏幕高宽比 
    //图片缩放后的宽为屏幕宽 
     imageSize.imageWidth = windowWidth-30; 
     imageSize.imageHeight = ((windowWidth-30) * originalHeight) / originalWidth; 
   }else{//图片高宽比大于屏幕高宽比 
    //图片缩放后的高为屏幕高 
     imageSize.imageHeight = windowHeight; 
     imageSize.imageWidth = (windowHeight * originalWidth) / originalHeight; 
   } 
     
  } 
 }) 
 return imageSize; 
} 

//当前时间
function formatTime(date) {

  var hour = date.getHours()
  var minute = date.getMinutes()
 

  return  [hour, minute].map(formatNumber).join(':')
}

//当前年月日
function formatday(date) {
  var year = date.getFullYear()
  var month = date.getMonth() + 1
  var day = date.getDate()

  return [year, month, day].map(formatNumber).join('-')
}

function formatNumber(n) {
  n = n.toString()
  return n[1] ? n : '0' + n
}


  
module.exports = { 
 imageUtil: imageUtil ,
 formatTime: formatTime,
 formatday: formatday
}